47-Million-Year-Old Owl Fossil Reveals Evolutionary Shift to Nocturnal Life
A 47-million-year-old owl fossil discovered in Germany's Messel Pit reveals that ancient raptors were diurnal, shedding new light on when owls evolved nocturnal habits.
A remarkably well-preserved 47-million-year-old owl fossil discovered at the Messel Pit in Germany offers unprecedented insights into the evolutionary timeline of nocturnal predatory birds. The newly described species, named Masillastrix blattophaga, was diurnal, as evidenced by an iridescent insect discovered in its stomach, along with its feather structure and wing bone morphology.
Published in the journal Current Biology, the study suggests that nocturnal behavior among owls evolved toward the end of the Eocene epoch, between 47 and 34 million years ago. While modern owls are renowned for exceptional nocturnal hearing and silent flight, the evolutionary transition from daytime to nighttime activity has long puzzled paleontologists because most known owl fossils consist only of isolated bones.
Exceptional Preservation at Messel Pit
The fossil, recovered during the 2025 excavation season at the German UNESCO World Heritage site, is nearly complete, lacking only the skull. Measuring approximately 12 centimeters in length, it represents only the second owl species ever discovered at the Messel Pit. The preservation is extraordinary, featuring intact wing and tail feathers as well as the remnants of a bright blue-green insect in its stomach.
Dr. Sonja Wedmann, who led the excavations for the Senckenberg Research Institute and Natural History Museum, noted that the insect remnants display strong longitudinal and numerous transverse veins characteristic of fossil cockroaches. A remarkably well-preserved cockroach found mere meters away confirmed the identification. Because colorful and iridescent wings in insects are typically associated with a diurnal lifestyle, the discovery provides crucial context regarding the predatory habits of the owl itself.
Evolutionary Timeline of Nocturnal Habits
Furthermore, the fossilized owl's feathers lack the specialized adaptations seen in modern nocturnal raptors, and its wing bone is significantly shorter than those of contemporary species. The earliest known owl displaying modern wing proportions lived in France approximately 35 million years ago, indicating that nocturnal activity developed during the Eocene.
While previous theories suggested owls turned nocturnal to avoid competition with diurnal raptors or to exploit a growing population of nocturnal mammals, researchers note that those mammal groups expanded significantly later—between 20 and 25 million years ago. This timing indicates no immediate ecological advantage drove the early shift. Although the exact catalyst remains a mystery, narrowing the temporal window brings researchers closer to solving a long-standing evolutionary puzzle.
